Meanwhile, volatile trading sent European stock markets on a roller coaster early on Wednesday, after the US Federal Reserve announced its rescue of bankuptcy-threatened AIG.

London's FTSE 100 index of leading shares was up 1.26 per cent to 5,089.10 points at mid-morning, swinging up again after reversing its initial gains, in a trend mirrored on other European markets.

In Paris, the CAC 40 was up 0.29 per cent to 4,099.36 points and Frankfurt's DAX 30 rose 0.25 per cent to 5,980.17, having both switched into losses earlier in the morning.

Russia's leading RTS stock market suspended trading following a plunge of six per cent, a stock market spokeswoman said.

Russia also moved to support the country's increasingly stressed banking sector, with the finance ministry in Moscow raising lending for the country's top banks, Sberbank, VTB, and Gazprombank, to $44.9bn.

The banks will be loaned federal funds for a minimum of three months, the ministry said.

'Better co-operation'

Central banks in Switzerland, Russia and Japan also poured more short-term cash into the markets, hoping to restore confidence between banks and encourage lending between them.

Credit markets had tightened on Monday, following the collapse of the investment house Lehman Brothers and central banks had already injected billions of dollars on Monday and Tuesday in an attempt to turn the tide.

By Wednesday, some appeared satisfied at the level of lending, while others continued to make more cash available.

A spokesman at the Swiss National Bank in Zurich said: "As in days past, the bank continues to provide generous and flexible liquidity to the markets.'

The Bank of Japan injected an extra $28.4bn into money markets to ensure liquidity, following on the heels of the $24bn it had pumped in the previous day.

Reflecting the depth to which the financial crisis has been felt, Angela Merkel, the German chancellor, told parliament she expects the crisis to effect Europe's biggest economy and called for politicians to construct "a smart frame of order'' for financial markets.

That, she said, should include better co-operation with regulatory agencies, more overall transparency, and for rating agencies and hedge funds to act more responsibly.